USC Trojans...under NCAA Investigation for McKnight....again.

USC athletic director Pat Haden vowed Saturday to launch an investigation into allegations that former tailback Joe McKnight and ex-basketball player Davon Jefferson received improper benefits from a controversial figure in the Los Angeles County assessor's scandal.

According to a emails obtained by the Los Angeles Times, former assessor's employee Scott Schenter provided McKnight with a car and airline ticket and gave Jefferson about $3,700.

"We have discussed those allegations with the NCAA and Pac-12, and we will thoroughly investigatethem and take any and all necessary actions," Haden said in a statement. "I can personally assure you that USC takes its compliance obligations with NCAAand Pac-12 rules extremely seriously and we are dedicated to playing and competing the right way."

Schenter is charged with giving improper tax breaks to wealthy Los Angeles residents in the investigation into former County Assessor John Noguez.

In 2009, USC investigated why McKnight drove a 2006 Land Rover owned by Schenter and submitted a report to the NCAA.

"All of the information related to the investigation was sent to the NCAA," Haden said. "The NCAA staff accepted the report, and no violation was processed."

Although the report did not find a violation, McKnight did not play in the 2009 Emerald Bowl because USC would not allow him to and he turned pro after the season. He currently plays for the New York Jets.

The emails also suggest Schenter bought McKnight a $625 airline ticket to New Orleans and cash to Jefferson.

"Just last week, as the fall sports season kicked off, (vice president for athletic compliance) Dave Roberts and I met again with our football team and staff to discuss and emphasize the importance of these rules and the need to be ever-vigilant in fulfilling our compliance obligations," Haden said. "Similar meetings will beheld with all of our athletic teams this fall."